[Pw_forum] Problems with integrated charge for a large supercell relaxation
schmidt at chem.wisc.edu
Fri Nov 21 22:02:46 CET 2008
Just to follow up on the problem of the integrated charge --
> Your system is treated as an insulator. If for some reason it
> becomes metallic or semimetallic, you may run into trouble.
> Add a few more bands and a small broadening, just in case.
I went back and verified this system. Even at the geometry where the
optimization failed, I took that geometry and did and SCF calculation
with extra bands. The band gap (at that geometry ) is 3.1 Ry (as would
be expected for this strong metal oxide insulator), so I don't think
that is the problem.
As I mentioned in the initial email, it is also odd that I can restart
the SCF or optimization from the 'failed' geometry and go for quite a
few optimization cycles before another crash
> Note that
> K_POINTS Gamma
> (uses "Gamma tricks") will be faster and take less memory
Fantastic! I was looking for a different (gamma-specific )executable,
but I couldn't find one. Now I know why.
Assistant Professor of Chemistry
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E-mail: schmidt at chem.wisc.edu
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